Given a task posture, changes in hand force magnitude and direction with regard to joint locations result in variations in joint loads. Previous work has quantified considerable vertical force components during push/pull exertions. The objective of this work was to quantify and statistically model actual hand forces in two-hand, standing exertions relative to the required nominal horizontal and vertical hand forces for a population of widely varying stature and strength. A total of 19 participants exerted force on a fixed handle while receiving visual feedback on the magnitude of force exerted in the required horizontal or vertical direction. A set of regression equations with adjusted R(2) values ranging from 0.20 to 0.66 were developed to define actual hand force vectors by predicting off-axis forces from the required hand force magnitude. Off-axis forces significantly increase the overall magnitude of force exerted in two-hand push/pull and up/down standing force exertions. STATEMENT OF RELEVANCE: This study quantifies and statistically models actual hand forces in two-hand, standing exertions. Inaccuracies in hand force estimates affect the ability to accurately assess task-oriented strength capability. Knowledge of the relationship between nominal and actual hand forces can be used to improve existing ergonomic analysis tools, including biomechanical simulations of manual tasks.
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http://dx.doi.org/10.1080/00140139.2010.535021 | DOI Listing |
Appetite
January 2025
University of Parma, Department of Food and Drug, Italy; Italian Academy for Advanced Studies in America at Columbia University, New York, USA. Electronic address:
Previous research has shown that organic food labeling may lead consumers to biased processing of their preferences, the physiological mechanisms behind this phenomenon are not understood. For the first time, this manuscript combines consumer valuation and physiological measures to investigate the explicit and implicit preference dimensions of organic food. The explicit dimension was measured using the expected and actual degree of liking of two identical - but differently labeled - pear juices (organic and non-organic) while the implicit dimension was measured using the activity of the mylohyoid muscle (MM) and the 3D kinematics of the hand, and arm movements.
View Article and Find Full Text PDFLife (Basel)
January 2025
Occupational Medicine Unit, Department of Medical and Surgical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy.
Musculoskeletal disorders are the most prevalent occupational health problem and are often related to biomechanical risk factors. Over the last forty years, observational methods for exposure assessment have been proposed. To apply them effectively in the field, an in-depth knowledge of each methodology and a solid understanding of their actual predictive value and limitations are required.
View Article and Find Full Text PDFGeorgian Med News
November 2024
4Department of Pathology, University of Virginia, Charlottesville, USA.
The toxicokinetics of nitrosamines remain a mystery to this day, though it appears that the role of nitrosamines in potentiating the generation of mutations required for the onset of skin cancer continues to be a significant concern. Nitrosamines are mutagens, genotoxic substances, and mediators of phototoxicity/carcinogenicity, whose long-term daily usage, in the context of polypharmacy, can result in the parallel appearance of heterogeneous forms of skin cancer: keratinocytic and melanocytic. But a number of clinical observations suggest that it is the nitrosamines that potentiate the multiple occurrences of skin cancer over the years, or recurrences of skin cancer localized in areas exposed to solar radiation.
View Article and Find Full Text PDFFront Immunol
January 2025
Section of Immunology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.
Background: Maintenance immunosuppression is required for suppression of alloimmunity or allograft rejection. However, continuous use of immunosuppressants may lead to various side effects, necessitating the use of alternative immunosuppressive drugs. The early secreted antigenic target of 6 kDa (ESAT-6) is a virulence factor and immunoregulatory protein of mycobacterium tuberculosis (Mtb), which alters host immunity through dually regulating development or activation of various immune cells.
View Article and Find Full Text PDFSci Rep
January 2025
Institute of Architectural Engineering, Shanghai Zhongqiao Vocational and Technical University, Shanghai, 201514, China.
Prefabricated buildings have a series of advantages such as high efficiency, energy savings, and environmental protection, and are being strongly promoted by the Chinese government. However, due to the late start of prefabricated buildings in China, the installation process of prefabricated components is relatively complex, leading to difficulties in quality and safety control. A novel evaluation methodology integrating the technique for order preference by similarity to ideal solution (TOPSIS) with prospect theory and interval-valued Pythagorean fuzzy numbers (IVPFNs) is proposed.
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